Multi-day trips and sleep

actually, I looked at the Katy Trail and seems a really good one! Probably not requiring a GPS satellite locator (pretty populated area) but still I think once in a while may be a life saver.
I don't know about a satellite locator but would call the Katy Trail unpopulated and isolated. That is its charm. In fact, whenever I plan that ride, I worry more about finding food and lodging than what equipment to buy. I recommend you consult

Amenities continually disappear or change. I did a short ride last summer from McKittrick to Tebbets and back. I counted 7 bar and grills/spit and whittle cafes/groceries that had closed since the last time I was there. The website I listed has almost all the information you need.

Don't miss crossing the new bridge to Herman and its wineries. Also, at least stop for a rest at the Turner Katy Trail Hostel, even if you wouldn't spend the night there. If you were to stay there, bring food. The hill billy honky tonk across the street and small grocery are among the closed establishments.